In medicine and surgery, it is sometimes desirable to inject 2 or more drugs or other substances simultaneously, from separate syringes. The prior art has included a number of devices that may generally be used to accomplish this. For example, the prior art has included a number of syringe pumps that may be used to simultaneously expel fluid from 2 or more syringes. Examples of commercially available dual-syringe or multiple-syringe pumps include: the KDS 200 Two-Syringe Infusion Pump, the KDS 101 Two-Syringe Nanoliter Pump, the KDS 220 Multi-Syringe Infusion Pump and the KDS 250 Four-Syringe Nanoliter Infusion Pump (KD Scientific, Inc., Holliston, Mass.); the SP 100i Infusion Pump (World Precision Instruments, Inc., Sarasota, Fla.) and the NE-1600 Multiple Syringe Pump (New Era Pump Systems, Inc., Wantagh, N.Y.).
The prior art has also included dual barrel syringes and apparatus that may be attached to two separate syringes and used to compress the plungers of both syringes simultaneously. For example, U.S. Pat. No. 4,609,371 (Pizzino) describes a dual syringe for either simultaneous or sequential injection of two different injectable liquids. The syringe includes two barrels, each having a plunger for the injection of liquid, and a manually operable three-position rotary valve which controls the filling of the syringe and the outflow of liquid from the syringe. The three positions of the valve permit liquid to be dispensed either from the first barrel only, the second barrel only, or both barrels simultaneously.
Also, U.S. Pat. No. 4,610,666 (Pizzino) describes a syringe having two or more barrels for injection of two or more liquids into a patient in predetermined sequence. The syringe includes a valve, either a slide valve or a rotary valve, which places the barrels one at a time in predetermined sequence in communication in the needle of the syringe. Preferably the syringe is pre-filled with the desired injectable liquids and the valve is preset so that the barrel containing the first liquid to be dispensed is in communication in the needle.
Additionally, United States Patent Application Publication No. 2006/0116646 (Weiss) describes bi-inoculator dual syringe clip of the invention is a unique piece of equipment that is a lightweight, convenient, sterile, and easy to use device that clips two existing syringes together which allows two inoculations to be combined into one step without having to combine the antibodies. The bi-inoculator dual syringe clip comprises a first and second half having at least a first and second pair of curved portions separated by a first and second spacer member. A hinged portion connects the first and second halves together such that the halves can be folded together causing the first pair of curved portions to mate with the second pair of curved portions to form a pair of tubular holding members capable of holding a syringe therein. The bi-inoculator dual syringe clip of the invention improves the method of administering inoculations tremendously and also improves patient care as well as reduces trauma.
Also, United States Patent Application Publication No. 2007/0005020 (Laveault) describes a dual syringe adapter for attachment to a pair of side-by-side syringes includes three interconnected portions. A first portion is configured so as to snap onto a plunger head portion of each syringe so as to connect the pair of syringes and maintain plunger movement in unison. A second portion of the adapter is configured so as to snap onto a syringe body of each syringe to help maintain the connection of the two syringes. The third interconnected portion is positioned between the first and second portions and when connected prevents relative movement of the plungers into the syringe bodies. Weakened sections allow the connecting portion to be severed from the first and second portions thereby allowing plunger movement into the syringe bodies. Once severed, the connecting portion is secured to syringe tips for dispensing a mixed composition.
One procedure currently under development wherein it is desirable to simultaneously inject a plurality of substances involves the deposition of platelet gel (PG) within an infarcted area of myocardium to improve myocardial function and/or to prevent deleterious ventricular remodeling following myocardial infarction or other injury to the myocardium. In this therapy, a platelet-containing component (e.g., platelet rich plasma (PRP)) is injected simultaneously with a thrombin-containing component (e.g., a thrombin solution) such that the platelet-containing component and the thrombin-containing component become mixed in situ (or within the lumen of a needle immediately before entering the myocardium). Such simultaneous injection and in situ mixing of the platelet-containing component and the thrombin-containing component results in the formation of PG, which causes the desired therapeutic effect. More specifically, the PG forms when active substances contained in the platelet-containing component (e.g., fibrinogen) are activated by thrombin contained in the thrombin-containing component. Autologous PRP can be obtained from the subject's own blood, thereby significantly reducing the risk of adverse reactions or infection. When autologous PRP is used as the platelet-containing component, the resultant PG is referred to as autologous platelet gel (APG). The addition of thrombin to platelet-containing plasma products such as PRP is described in detail in U.S. Pat. No. 6,444,228 and United States Patent Application Publication Nos. 2007/0014784, 2006/0041242 and 2005/209564, the disclosures of each such patent and patent application being expressly incorporated herein by reference. Since it is difficult to pass PG or APG through the lumen of a needle, it is desirable to inject the platelet-containing component and the thrombin-containing component such that they become mixed immediately prior to, during or after injection through the needle. Additionally, injecting the platelet-containing component and the thrombin-containing component separately or immediately after mixing may allow the infusate to distribute to a greater area before fully gelling into the PG or PG, thereby possibly enhancing the effect of this therapy. Multiple component injectors that are suitable for simultaneous injection of PRP and thrombin solution are described in U.S. patent application Ser. No. 11/969,094, the disclosure of which is also expressly incorporated herein by reference. U.S. patent application Ser. No. 11/969,094 describes a multiple component injector device that uses 2 primary injector syringes and two larger reservoir syringes. The plungers of the two primary syringes are compressed simultaneously in increments to effect repetitive injection of aliquots of the PRP and thrombin solution into the myocardium. When the contents of the primary syringes have been depleted, if it is desired to continue the injection process, the user must refill the primary syringes from the reservoir syringes. This refilling process can require the user to manipulate valves on stopcocks, draw the desired amounts of material from the reservoir syringes into the primary syringes, return the stopcock valves to their original positions and then proceed with further injections of the materials into the myocardium. Control over the volume of each injection and the volume of each refill are dependent on the operator's ability to precisely move the syringe plungers while carefully observing graduated markings on the syringe(s).
There remains a need for the development of new devices and methods for precisely controlled simultaneous injection from two or more syringes while allowing for easy syringe exchange when desired.